I use mine for making kefir yogurt, with a couple of tablespoons of Yeo Valley kefir (plain) and a 1L box of long life milk. I eat kefir every day and a 350g pot costs £2, so being able to make a litre for 99p makes it a lot less expensive.
I also use it for cooking dried beans, again because it is so much cheaper than buying tins or packets of ready cooked beans. I have all the different varieties of beans, dried peas and lentils in the kitchen cupboard, measure out the ones I want to cook the next day and soak them overnight. You can get away with not soaking them if you don't mind cooking them for longer, but I find they absorb other flavours better if they have been soaked first. I love Greek plaki (those giant butter beans in tomato sauce) but don't like paying several quid for a small tin of them, so I make my own with real Gigantes beans imported from Greece (via Amazon, but only at certain times of the year). I also use the instant pot for making Mexican beans, and Indian dahl and bean curries.
The instant pot makes excellent risotto too, with no faffing about adding a tiny bit more liquid every few minutes. I make mushroom risotto with rice, and pearl barley risotto with Italian vegetables and herbs. Oh and it also makes perfect quinoa, with no standing over the pot watching for the little tails to unfurl.
The instant pot tends to make 6 very generous portions of risotto or beans, for the price of a single ready meal bought from the supermarket. The only problem is finding space in the freezer for the surplus single portion bags and pouches.
I also use it for cooking new potatoes (in the steamer basket with a sprig of garden mint) in just 7 minutes, and perfect broccoli in 1 minute, also in the steamer basket.
I'm the kind of cook who gets distracted easily, anything that needs to be stirred and watched is at risk of burning or going mushy. With the instant pot all you need are really good recipes where someone else has calculated exactly how much liquid you need, and how long to cook it.
When I bought it a friend recommended adding the extra steel inner pan and matching glass lid, as well as the steamer basket. I have not regretted getting them, it is so handy to use oven gloves to lift out the interior steel pan full of beans, and pop in the other inner pan, with the measured grains and liquid to make quinoa/risotto/rice or with the steamer basket for spuds, sweet potatoes and carrots.
I also have a silicone form for making egg bites in the instant pot, with cheese, herbs and very finely chopped vegetables.
Oh, and then there are the instant pot black bean chocolate brownies, all fudgey and delicious. I haven't made them for ages I wonder if I still have the recipe?
My brother made the mistake of buying a different electric pressure cooker that claimed to be able to do more things than the instant pot. He never uses it because his machine won't work if it has less than 600ml of water in the bowl and all that extra liquid takes ages to come up to pressure, compared to the instant pot that will steam with only one cup of water in the bottom of the pan.